Growth performance and intestinal histology in broiler chickens fed with dietary chitosan.

1. The effect of a low dietary chitosan content (06 g/kg) on growth performance, carcase quality, visceral organs and intestinal morphology was studied. 2. A total of 24 male Marshall Chunky broiler chicks were fed on a commercial basal diet with 0 (control) and 06 g/kg chitosan until 7 weeks of age. Body weight gain and feed intake were higher in the chitosan group but there were no differences in feed efficiency and breast meat, drumsticks and visceral organ weights. 3. There were no difference in intestinal villus height, villus area, cell area or cell mitosis except for significantly increased duodenal cell mitosis and ileal villus area in the chitosan group. 4. In the chitosan group, epithelial cells on the villus apical surface in the duodenum showed many kinds of morphological patterns such as protuberated cells, cell clusters, and deeper cells at sites of recently exfoliated cells. The ileal villus apical surface had protuberated cells, and most cells were attached by segmented filamentous bacteria. These villi showing rough surface of the duodenum and ileum were more in the chitosan group than in the control, although not statistically significant. 5. These results suggest that a low content of dietary chitosan improved growth performance, and this may be attributed due to the presence of hypertrophied villi and epithelial cells.

Effects of dietary natural zeolite including plant extract on growth performance and intestinal histology in Aigamo ducks.

1. To investigate the growth performance and histological intestinal alterations of Aigamo ducks fed on dietary combinations of zeolite, plant extract and vermiculite (ZEM, 14-d-old Aigamo ducks were divided into 4 groups, with 3 replicates of 3 male and 3 female ducks. They were fed ad libitum on a basal commercial duck mash diet with 0, 0.1, 0.5 and 1.0 g/kg dietary ZEM for 63 d. 2. Body weight gain tended to be higher for the 0.1 and 0.5 g/kg ZEM groups than for the control group at 9 weeks. 3. In light microscopic observation, most values of the intestinal villus height, villus area, cell area and cell mitosis numbers were higher in the ZEM group than those of the control in all intestinal segments, and the duodenal villus height, cell area and cell mitosis of the 0.5 g/kg ZEM group, as well as jejunal cell mitosis in the 0.1 g/kg ZEM group, increased (P < 0.05). In the scanning electron microscope results, all ZEM groups showed protuberant epithelial cells and cell clusters on the villus apical surface of the duodenum and ileum. In the jejunum, villus gyri were frequently observed in the 0.1 g/kg ZEM group. These histological intestinal alterations suggest that intestinal villi and epithelial cellular functions might have been activated. 4. From the present results, dietary ZEM showed hypertrophied functions of intestinal villi and epithelial cells at the duodenum and ileum, and the 0.1 and 0.5 g/kg levels improved body weight gain. These suggest that the ZEM can be supplemented until a level of 1.0 g/kg.